Montana distribution: Small sand dune areas 

 and to unknown extent on major eastern rivers; 

 including three locations in Carter, Cascade, and 

 Custer counties. 



Carter County distribution: One population is 

 known at Medicine Rocks State Park. Note: It is 

 known from downstream on the Little Missouri 

 River in North Dakota (North Dakota Natural 

 Heritage Program 1990, 1993), but there are no 

 BLM-administered lands adjoining this river in 

 Montana. 



Chenopodlum tubglabrum 

 Smooth Goosefoot 



HABITAT: Chenopodium subglabrum grows in extremely loose, sandy soils. In Montana, two of 

 the populations (including the Medicine Rocks occurrence) are on sand dune habitats, and the third is 

 on a sandbar or sandy terrace along the Powder River that might no longer be extant. The species 

 was not found on BLM lands surveyed in 1997, and is unlikely to occur on BLM-administered lands. 



SPECIES BIOLOGY: Smooth goosefoot is an annual species. It occurs in low numbers and low 

 density (North Dakota Natural Heritage Program 1 990), and its persistence is vulnerable to extreme 

 wind or water erosion scouring events, as well as to long-term vegetation change that increases cover 

 and competition. Like other species of the genus, it is wind-pollinated and is likely to have seeds 

 that can survive more than one year until they germinate. It produces relatively few seeds per plant, 

 so seedling establishment is presumed critical in species' life history. 



OTHER COMMENTS: This species is very unlikely to occur on BLM-administered land in Carter 

 County. But this study does not address BLM-administered lands throughout the state, so we do not 

 have any new information for recommending change to its statewide status. 



Noxious weeds like leafy spurge {Euphorbia esula) can over-run this species sandy habitat and they 

 threaten the species elsewhere in its range. This threat is low or absent at the Medicine Rocks State 

 Park to date. Tamarisk {Tamarix chinensis) is invading the locale on the Powder River where the 

 species was collected in 1973. 



This is one of several sand-loving species in the county that are often found with other species of 

 special concern where the habitat is extensive and/or in good condition. 



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